辽东湾大凌河口湿地土壤微生物群落分析

土壤微生物对湿地生态系统的物质转化和能量流动具有重要作用,目前对天然湿地的微生物资源及群落结构缺少研究。应用PCR-DGGE技术研究辽东湾大凌河口湿地土壤中的微生物群落结构,并对其群落组成进行分析,结合冗余分析（RDA）方法考察环境因子对微生物群落结构的影响。共设定7个站位采集土壤样品,直接提取样品中微生物的总DNA,以巢式PCR扩增细菌16S rDNA-V3区片段,应用变性梯度凝胶电泳（DGGE）技术分离片段,研究河口区湿地土壤细菌的群落结构。结果表明：辽东湾大凌河口区土壤具有较为丰富的细菌种群,主要包含Proteobacteria、Actinobacteria和Bacteroidetes几大类门,且同一季节采集的样品在聚类分析图上聚类成簇。RDA分析表明,土壤的温度与盐度2个变量分别解释了6.5%、2.3%的土壤细菌群落结构变化,表明大凌河口区土壤的群落结构变化是多种环境因子共同作用的结果,其中温度的影响略大于盐度。

Analysis of bacterial communities in Liaodong Bay Dalinghe estuarine wetland

Microbial community serves as the driving force for material transformation and energy flow in wetland ecosystem.Currently,studies on microbial resources and community structure of natural wetlands are limited.By using PCR-DGGE and redundancy analysis（RDA）,this paper studied the variations of soil bacterial community structure of Dalinghe estuarine wetland in Liaodong Bay,and analyzed the soil factors affecting the diversity of the bacterial community.Seven stations were set to collect soil samples.The community DNA was extracted from the soil samples directly and used as template to amplify bacterial 16S rDNA-V3 gene fragment by nested PCR.Analysis of 16S rDNA PCR-DGGE showed that the bacterial population diversity was abundant in Dalinghe estuarine wetland.Most of the soil microorganisms belonged to the Proteobacteria,Acinobacteria and Bacteroidetes.Samples collected in the same season grouped into the corresponding clusters.RDA analysis showed that the soli temperature and soil salinity could respectively explain 6.5% and 2.3% of the total variation of soil bacterial community,indicating that most of the variation was due to the synergy of various environmental factors.